Question

In the equation `2KClO_3 -> 2KCI + 3O_2`, how many moles of oxygen are produced when 5.05 m of `KClO_3` decompose completely?

Answer 1

7.58 moles of `O_2` are produced.

Explanation:

There are multiple lines of reasoning for solving this. Let me give you the most detailed:

You start with a plan: we will convert moles of `KClO_3` to moles of `O_2` using the balanced chemical equation:

You will get 3 moles of `O_2` for every 2 moles of `KClO_3` you decompose.

Now let's substitute the number of moles of `KClO_3` that you actually started with:

`5.05 " moles "KClO_3 xx (3 " moles " O_2)/(2 " moles " KClO_3) = 7.575 " moles " O_2`

Finally, since we started with three significant figures, we have to end up with three significant figures since all we did was multiply and divide, so...

7.58 moles `O_2`